Fan wheel with arcuate blade forming strips



y 15, 1951 J. F. SKOLD 2,552,651

FAN wan-:1. wrm mum BLADE FORMING smrs Filed Sept. 10; 1947 2 shuts-shun 1 May 15, 1951 J. F. SKOLD 2,552,651

FAN mm. mm ARCUATE BLADE FORMING smrs Filed Sept. 10, 1947 2 Sheets-Sheet Z Patented May 15, 1951.

FAN WHEEL wrrn ARCUATE BLADE FORMING s'rarrs John F. Skold, Chicago, 111.

Application September 10, 1947, Serial No. 773,172

Claims. 1

The present invention relates generally to fan wheels. More particularly the invention relates to that type of fan Wheel whichis adapted to be driven at a comparatively high speed by an elecforce it forwards under pressure or increased velocity.

One object of the invention i to provide a fan wheel of this type which is generally an improvement upon, and has a certain inherent advantage over, previously described fan wheels and is characterized by extremely high efficiency as well as lack of mechanical noise.

Another object of the invention is to provide a fan wheel of the aforementioned type in which the blades are substantially circular, have large sized openings or apertures in their central portions and are in the form of substantially continuous arcuate sheet metal strips.

Another object of the invention is to provide a fan wheel of the last mentioned type and character in which the hub structure embodies pairs of opposed lugs which correspond in number to, and are associated respectively with, the bladeforming strips and are so arranged that one lug of each pair is inclined or angled re'arwards and has the leading end of the associated bladeforming strip connected thereto and the other lug is inclined or angled forwardsand has the trailing end of the associated blade-forming strip connected to it.

Another object of the invention is to provide a fan wheel of the character last mentioned in which the root portions of the rearwardly inclined lugs of the hub structure are disposed in substantially the same plane as the root portions of the forwardly inclined lugs in order that the leading and trailing ends of the blade-forming strips are laterally offset and hence cause the central portions of the strip to be so bent or twisted that the pressure faces thereof are concave or scoop-shaped.

A further object of the invention i to provide a fan wheel of the aforementioned type and character in which the hub structure embodies a pair of sidegby side or juxtapositioned sheet metal stampings, one of which is shaped to progel. 170-171) l 2 vide the rearwardly inclined lugs and the other of which is shaped to provide the forwardly inclined lugs. V

A still further object of the invention is to provide a fan Wheel which is of generally new and improved construction, may be produced at a comparatively low cost, and due to its construction and design is ornamental in appearance and also light in Weight.

Other objects of the invention and the various advantages and characteristics of the present fan wheel will be apparent from a: consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof. v

In the drawings which accompany and form a part of this specification or disclosure and in which like numerals of references denote'corresponding parts throughout the several views:

Figure 1 is a front view of a fan wheel embodying the invention;

Figure 2 is a side View illustrating in detail the manner in which the central portions of the blade-forming strips are caused to be concave or scoop-shaped as a result of the fact that the leading and trailing ends of the strips due to the arrangement or positioning of the lugs are in laterally oifset relation; 1 1

Figure 3 isa side view similar to Figure 2 except that one of the blade-forming strips is shown in section; v

Figure iis a rear view of the hub structure withoutthe blade-forming strips; 7 I

Figure 5 is a side view of the hub structure showing the construction and side by side relationship of the complemental lug-equipped sheet metal stampings; v s

Figure 6 is a front view of one of the substantially continuous arcuate. sheet metal strips of which the blades of the fan wheel are formed; and Figure 6a is an end view of the strip of Figure 6 illustrating the manner in which the central or outer portion is bent or twisted ,due to the ends being laterally or axially offset.

The fan wheel which is shown in the drawings constitutes the preferred form or embodiment of the invention and is adapted to be used in connection with moving of air or other fluid. .It is particularly designed for circulating air in a roomror otherenclosure andasits component parts comprises a hub structurefl and a plurality. of equidistantly spaced radially extending blades 8. It is contemplated that the fan wheel will be driven or rotated at a comparatively high rate of speed by an electric motor or any other suitable source of power (not shown). The fan wheel is shown in the drawings as embodying four blades 8. It is to be understood, however, that the fan wheel may embody more or less blades. For purposes of the present disclosure, it will be assumed that the fan wheel embodies the four blades that are 'shown. It will also be assumed that the fad wheel, in connection with operation thereof, is driven in a clockwise direction as viewed in Figure 1.

The hub structure I is of unitary interim-.1

posite character and comprises a sleeve Wanda pair of complemental sheet metal stampingsTI-O and II. The sleeve 9 has a centrally disposed, longitudinally extending openendedjbore .12 for accommodating and receiving the shaft of the electric motor or other, power source whichis formed integrally with, the side margins of the central part 29 and are inclined forwards in such manner that all parts thereof are at an angle of approximately 35 with respect to a plane extending at right angles to the axis of rotation of the fan wheel. They are flat, and in addition to being forwardly inclined, extend laterally in the direction of rotation of the fan wheel. The outer ends of the lugs 2!, like the outer ends of the lugs I 8, are preferably curved or rounded. Each rearwardly inclined lug l8 and the opposed or diametrically opposite forwardly inclined lug 2| constitute a pair of opposed lugs for anchoring in place or mounting 1'0 and H are in abutting relation, the root or innea; end -port;ion-sof the rearwardly inclined rear end'ofthe sleeve. The front central portion ofthe sleeve isprovid'ed with an exteriorly disposed enlargement l5, the front end orface of which" is spaced rearwards of the front end face of the sleeve and defines a forwardly facing ing Illis flat and has a centralcircular hole (9 through which the front end of the sleeve 9 extends. The diameter of the hole [9 is substantially the same as the external'dia-meter of' the front end of the sleeve. The rear face of the central part IT abuts against the annular forwardly' facing shoulder |6 as"shown in Figure 5. The-lugs l-8 are connected'to and project outwards from the side margins of the central part Hf and'aref' bent or inclined rearwards sh that all" arts thereofextend at anangle -of approximately 35'' with respect to a plane extending at right angles to-the axis of rotation of the fan wheel. Theyare flat throughout and in addition to being're arwardly inclined extend laterally in'a direction opposite to the direction of rotation of the tan" wheel. Preferably the outer ends of the lugs it are curved or rounded. The other sheet metal stamping, that is the stamping I I is the complement of the stamping Ill. It.is,.hor vever,

reversely nositionedan'd consists of a square central part 2!] .andfour outwardly extending lugs 2!. .It is of a one piece character. andis disposed in front of, and in abutting relation with, the stamping Ill. The central part 2a of the stamping .H ,is disposed in registering relation with'the central partv IT of the stamping Ill and has a central circular hole 22 through which the front end of the sleeve 9'extends. The holeZZ is the same in size as the hole 19 and is of such diameter that the .portion of the central part 20 that defines it fits snugly around the front end of the sleeve. The extreme front end .ofoIthe sleeve is riveted or beaded over as at 23 and serves to clamp the central parts of the two stampings. against the annular forwardly facing shoulder It. The clam-ping action issuchthat .thetwo sta mpings Illand I lare mounted fixedly in place andhence are .precluded from rotating. relatively. to the sleeve Thelugs 2[ are .joined to, and

lugs l8 lie in substantially the same plane as the rootorinner end portions of the forwardly inclined lugs 2|. The blades-I8 are substantially circular and have large sized substantially circular apertures 24 in their central portions. They are in the form of substantially continuous arcuate sheet metal strips and have forwardly facing pressure faces 25 and rearwardly facing suction faces 26. Such strips extend throughout arcs of approx-i: .rnately 330 and preferably have curved or rounded ends. The apertures 24 are eccentric-ally positioned with respect to the outer edges of the blade-formingstrips. They are inwardly offset with respect to the true centers of the'blades to the end that'the endsfof theblade-forming strips are narrower tha'nth'e central 'or outer portions of the strips. The blades are angularly' disposed with respect to the'plane of rotation of'the wheel in order that during drive or'rotation of the wheel: they serve to draw air from in backof the wheel and force it forwa'rdsunder pressure or increased velocity. Eachblade-formin'g strip is associated with and connected to one pair of opposed or diametrically opposite huge. The leading'ends of the blade-forming strips fit flatly against the front'facesbf; andare connected by pairs of rivets 27 to, the rearwardly' inclined lugs 18 and the trailing ends" of the blade-forming strips fit flatly against the front faces of, and are secured by pairs of rivets 28 to, the forward ly inclined lugs 2l'. When the" fan wheel em bodies four blades, the leading ends of the bladeforming' strips are in lapped r'ela'tion with the trailing ends of thestnps; as shown in Figure'l. Due to the position, arrangement and angularity of the lugs l8 and Zlfthe leading ends of the blade-forming strips are axiallyfor laterally offset with respect to the trailing ends of the strips. Hence, the central or outer portions of the strips are so bent or twisted that the central or outer portions of the pressure faces 25 are concave or scoop-shaped. By having the central or outer the hub structure and the blades is characterized by extremely high efficiency. It is light in weight and also ornamental in appearance. By forming the hub structure I, for the most part, of sheet metal stampings and by forming the blades of substantially continuous arcuate sheet metal strips, the fan wheel may be produced at a comparatively low cost.

Whereas the wheel has been described as a fanwheel for circulating air in a room or other enclosure, it is to be understood that it may be used in any other form or type of fluid either as a medium for displacing the fluid or as a propeller.

It is also to be understood that the invention is not to be restricted to the details set forth, as these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention what I claim as new and desire to to secure by Letters Patent is:

1. A fan wheel adapted for rotation in one direction in a fluid and comprising a hub structure provided with means whereby it may be connected a power driven shaft for rotation about its own axis and embodying on one part thereof attaching means and directly rearwards of said means a set of laterally spaced, outwardly extending, flat, rigid lugs inclined in such manner a plurality of radially extending, angularly disposed, centrally apertured blades corresponding in number to said set of lugs and formed of substantially continuous, flexible, arcuate strips arranged with the ends thereof adjacent the hub structure and having their leading ends fitting flatly against, and connected fixedly to, said lugs and their trailing ends fixedly connected to the attaching means.

2. A fan wheel adapted, for rotation in one direction in a fluid and comprising a hub structure provided with means whereby it may be connected to a power driven shaft for rotation about its own axis and embodying on one part thereof attaching means and directly rearwards of said means a set of laterally spaced, outwardly extending, flat, rigid lugs projecting laterally in a direction opposite to the direction of rotation of the fan wheel and inclined in such manner towards the rear end of the hub structure that all parts thereof extend at the same acute angle with respect to a plane extending at right angles to the axis of rotation of said hub structure, and a plurality of radially extending, angularly disposed, centrally apertured blades corresponding in number to said set of lugs and formed of substantially continuous, flexible, arcuate strips arranged with the ends thereof adjacent the hub structure and having their leading ends fitting flatly against, and connected fixedly to, said lugs and their trailing ends fixedly connected to the attaching means.

3. A fan wheel adapted for rotation in one direction in a fluid and comprising a hub structure provided with means whereby it maybe connected to a power driven shaft for rotation about its own axis and embodying a set of laterally spaced, outwardly extending, flat rigid lugs inclined in such manner toward the rear end of the hub structure that all parts thereof extend at the same acute angle with respect to a plane ,6 extending at right angles to the axis of rotation of the hub structure, andin addition a corresponding set of laterally spaced, outwardly extending, fiat, rigid lugs positioned directly in front of the first mentioned lugs and inclined in such manner toward the front end of the hub structure that all parts thereof extend at the same acute angle with respect to said plane, and a plurality of radially extending angularly disposed centrally apertured blades corresponding in number to each set of lugs and formed of substantially continuous, flexible, arcuate strips arranged with the ends thereof adjacent said hub structure and having their leading ends fitting flatly against and connected fixedly to said first mentioned lugs and their trailing ends fitting flatly against, and connected fixedly to, the second mentioned lugs.

4. A fan wheel adapted for rotation in one direction in a fluid and comprising an elongated hub structure provided at the rear end thereof whereby it may be connected to a power driven shaft for rotation about its own axis and embodying a set of laterally spaced outwardly extending, flat, rigid, lugs projecting laterally in a direction opposite to the direction of rotation of the fan wheel and inclined in such manne towards the rear end of the hub structure that all parts thereof extend at the same acute angle with respect to a plane extending at right angles to the axis of rotation of said hub structure, and in addition a corresponding set of laterally spaced, outwardly extending, flat, rigid lugs and positioned directly in front of the first set of lugs, projecting laterally in the direction of rotation of the fan wheel and inclined in such manner toward the front end of the hub structure that all parts thereof extend at the same acute angle with respect to said plane, and a plurality of radially extending, angularly disposed, centrally apertured blades corresponding in number to each set of lugs and formed of substantially continuous, flexible, arcuate strips arranged with the ends thereof adjacent said hub structure and having their leading ends fitting flatly against and connected fixedly to said first mentioned lugs and their trailing ends fitting flatly against, and connected fixedly to, the second mentioned ugs.

5. A fan wheel adapted for rotation in one direction in a fluid and comprising an elongated hub structure provided at the rear end thereof with means whereby it may be connected to a power driven shaft for rotation about its own axis and embodying a transversely extending metal stamping having a flat polygonal central portion and a plurality of flat lugs connected to, and extending outwards from, the marginal portion of the central portion and inclined in such manner toward the rear end of the hub structure that all parts thereof extend at the same acute angle with respect to a plane extending at right angles to the axis of rotation of the hub structure, and in addition a second transversely extending metal stamping positioned directly in front of the first stamping, shaped conformably to, but positioned reversely of, said first stamping and consisting of a flat polygonal central portion :and a plurality of lugs connected to, and extending outwards from, the outer marginal portions of the second mentioned central portion and in clined in such manner towards the front end of the hub structure that all parts thereof extend at the same acute angle with respect to said plane, and a plurality of radially extending, angularly disposed, centrally apertured blades corresponding: in number to the lugs of each stamping and formed of substantially continuous flexible arcuate strips arranged with the ends thereof adjacent the hub structure and having their leading ends fitting flatly against, and connected fixedly to, the first mentioned lugs and their trailing ends fitting flatly against, and connected fixedly to,v the second mentioned lugs.

' JOHN F; SKOLD.

' REFERENCES CITED 7 The following references are of record in the iileofthis patent:

, UNITED STATES PATENTS Number Number Name Date Fola Dec. 1 1906 Armstrong June 17, 1919 Shaffer May 4, 1920 Barton July 5, 1927 FOREIGN PATENTS Country Date Great Britain of 1888 Great Britain of 1889 GreatBritain Dec. 31, 1937 

